Friday, June 08, 2007

In a breakthrough that sounds like something out of Star Trek, they have discovered a way of 'beaming' power across a room into a light bulb, mobile phone or laptop computer without wires or cables.

Rather than sending power from a transmitter to a receiver as a conventional electromagnetic wave - the same form of radiation as light, radio waves and microwaves - he could use the transmitter to fill a room with a 'non-radiative' electromagnetic field.

Most objects in the room - such as people, desks and carpets - would be unaffected by the electromagnetic field. But any objects designed to resonate with the electromagnetic field would absorb the energy.

It sounds complicated, but the result demonstrated by the American team this month was a dramatic success. Using two coils of copper, the team transmitted power 7ft through the air to a light bulb, which lit up instantly.

The scientists say the technique works only over distances of up to 9ft. However, they believe it could be used to charge up a battery within a few yards of the power source connected to a receiving coil. Placing one source in each room could provide enough power for an entire house.

The team from Massachusetts Institute of Technology, who call their invention 'WiTricity', believe it could change the way we use electricity and do away with the tangle of cables, plugs and chargers that clutter modern homes.

The MIT system is about 40 percent to 45 percent efficient, meaning that most of the energy from the charging device doesn't make it to the light bulb. Soljacic believes it needs to become twice as efficient to be on par with the old-fashioned way portable gadgets get their batteries charged.